Datasheet

90
4341H–MP3–10/07
AT8xC51SND2C/MP3B
15.1.7 Digital Mixer Control
The Audio DAC features a digital mixer that allows the mixing and selection of multiple input
sources.
The mixing / multiplexing functions are described in the following table according with the next
figure:
Figure 15-9. Mixing / Multiplexing functions
Note: Whenever the two mixer inputs are selected, a –6 dB gain is applied to the output signal. When-
ever only one input is selected, no gain is applied.
Note: Refer to DAC_MC register Table 15-20. for signal description
15.1.8 Master Clock and Sampling Frequency Selection
The following table describes the different modes available for master clock and sampling fre-
quency selection by setting OVRSEL bit in DAC_CSFC register (refer to Table 15-21.).
Table 15-7. Master Clock selection
The selection of input sample size is done using the NBITS 1:0 in DAC_MISC register (refer to
Table 15-22.) according to Table 15-8.
Table 15-8. Input Sample Size Selection
Signal Description
LMSMIN1 Left Channel Mono/Stereo Mixer Left Mixed input enable – High to enable, Low to disable
LMSMIN2 Left Channel Mono/Stereo Mixer Right Mixed input enable – High to enable, Low to disable
RMSMIN1 Right Channel Mono/Stereo Mixer Left Mixed input enable – High to enable, Low to disable
RMSMIN2 Right Channel Mono/Stereo Mixer Right Mixed input enable – High to enable, Low to disable
Volume
Control
Volume
Control
Volume
Control
Volume
Control
+
+
1
2
2
1
Left channel
Right channel
From digital
filters
To DACs
OVRSEL Master Clock
0 256 x FS
1 384 x FS
NBITS 1:0 Format
00 16 bits
01 18 bits
10 20 bits